Derivatives of the disesquiterpene gossypol will be synthesized. This primarily involves modification of the aldehyde functional groups of gossypol. Gossypol and derivatives will be evaluated in three different biological assay systems. 1. Gossypol and derivatives will be evaluated for their antiparasitic activity against the malarial parasite P.falciparum. Activity will be compared with the ability of the drugs to inhibit parasite lactate dehydrogenase, the putative target. 2. Gossypol and derivatives will be evaluated for their antiviral properties against herpes simplex type II. 3. Gossypol and derivatives will be evaluated for their properties as inhibitors of aldose reductase from human placenta. This enzyme is the target for drugs which may be useful in the treatment of diabetic complications.